any bioluminescent marine dinoflagellate of the genus Noctiluca
Word origin
C17: from Latin, from nox night + lūcēre to shine
noctiluca in American English
(ˌnɑktəˈlukə)
noun
any of a genus (Noctiluca) of large, spherical, reddish, luminescent dinoflagellates that often occur in vast numbers in the sea, causing the water to glow at night
Word origin
ModL < L, something that shines at night < nox (gen. noctis), night + lucere, to shine < lux, light1